The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
Toxins are chemicals or physical agents that exert a toxic effect on living organisms. Toxic means poisonous: that is, causing a reaction with cellular components that disrupts essential metabolic processes. At some level of exposure, all chemicals, whether natural or synthetic, are toxic. All can either cause death or damaging effects soon after exposure, or can cause some other disease (such as cancer or birth defects) after longer-term exposure.
Although many people think toxins are mainly pesticides or industrial chemicals, they also include the poisons of marine animals, spiders, snakes, plants, and the extremely toxic botulinum toxins that can kill a human being with a single minuscule dose. Toxins can exert their effects on many different organs. The nervous system, the brain, the lungs, the skin, and the eyes are only some of the organs that can be damaged by toxins. Toxicologists use reports, epidemiology, and laboratory studies to characterize both the lethal doses of toxins and the doses of certain chemicals that can cause disease over the long term. Environmental laws regulate exposures to certain human-made toxins.